HPC has been identified as one of the key pillars of the Digital Single Market (DSM) strategy adopted by the European Commission recognising its capacity to promote science, industrial innovation and ultimately
social prosperity. Societal challenges, human curiosity and industrial innovation demand solutions to problems with higher quality, in shorter time, and at larger scales. We require the solution of new and complex challenges in global climate change, air pollution, high-frequency trading, huge social networks, personalised healthcare, energy-efficient combustion engines, optimised design of new materials and many others. Several critical research areas and problem classes such as weather prediction with fine granularity, climate change, large eddy simulation for turbulence modeling in aeronautics, the challenges in fusion research, to name a few, are beyond current computing capabilities and need exaflop-level performance and even more. Unfortunately, scaling up to exascale is far from trivial and can by no means rely upon conventional scaling approaches embraced during the last fifteen years. Current practices for building supercomputers rely on architectures, microprocessors, accelerators and memory modules that were designed and optimised to cope with the demands of different markets (desktop, server, graphics, gaming, etc.) glued together with high-performance interconnection networks. While this was a viable and cost-effective approach to drive systems up to the current scale, it cannot lead to the exascale in a straightforward way.
HPC is well known for the gap between the theoretical peak performance of an actual platform and the achieved performance when running real applications. To reduce this disparity, a platform must be designed based on a thorough understanding of the applications and the system software, while the applications themselves must leverage the full capabilities of the underlying hardware and software stack. EuroEXA targeted the design and implement of a new system architecture that better balances the required computing resources compared to today’s systems, supporting the acceleration of key applications. To accomplish this, we followed a system-level co-design approach with appropriate employment of a wide range of typical and non-conventional HPC codes.